1. Field of the Invention
The present invention relates to a bellmouth which, mainly when a cable protection pipe passage for an electric wire, a telephone wire, an optical cable and the like is buried into the ground, is mounted on the side wall of a hand hole and a manhole to be installed as a cable relay station and allows a pipe for forming a pipe passage to be connected thereto. The present invention also relates to a concrete body using the bellmouth. The present invention further relates to a handhole or manhole using the bellmouth.
2. Description of the Related Prior Art
Conventionally, when a cable pipe passage is laid down in the ground, as a cable relay station, there are set up hand holes and manholes at every proper intervals in the cable pipe passage.
Note that in the specification and claims, both of the hand hole and the man hole are represented by simply hand holes, because these holes are similar in configuration and shape which are easily understandable by a person skilled in the art.
In setting up such hand hole, as known well, there are employed two types of setting-up-processes. The one of the setting-up-processes is that the ground is dug by a required depth to form a hole, and concrete is placed into the hole to thereby produce the peripheral wall body of the hand hole on site. The other of the seeting-up-processes is that a hand hole previously formed in a factory or the like is carried to the installation site and buried there.
Also, in either case, generally, at the same time when the peripheral wall of the hand hole is formed, there is formed in the side wall of the hand hole a through bore which communicates with the inside and outside of the hand hole and is necessary to mount a bellmouth to which a pipe for forming a cable pipe passage can be connected. However, in the former case, that is, in the member for forming the hand hole on site, it is also known to mount the bellmouth on the peripheral wall at the same time when the hand hole is formed.
Thus, in either case, the bellmouth to be mounted on the hand hole is formed as a substantially simple, cylindrical-shaped member including on one end side thereof a trumpet-shaped portion which is to be disposed inside the hand hole.
Therefore, to connect the pipe passage forming pipe to such cylindrical-shaped bellmouth, the end of the pipe is inserted into or fitted over the projecting portion of the bellmouth which projects externally from the hand hole, and a hardening agent solution for stopping the water is poured into between them or water stopping tape is wound around them.
However, the above operations respectively take time and labor and, especially, there are not found many cases in which only one bellmouth is mounted on a hand hole; but, in many cases, three mutually adjoining bellmouth, which are arranged in the horizontal direction, are mounted in two upper and lower stages, adding up to six bellmouths (that is, 3xc3x972=6), or, three mutually adjoining and horizontally arranged bellmouths are mounted in three vertical stages, adding up to nine bellmouths (that is, 3xc3x973=9). In these cases, it is difficult to connect all pipes to the bellmouths in a perfectly watertight condition and such connecting operation requires a lot of time and labor. Also, even if an operation to connect the pipes to the bellmouths is completed, unless hardening agents used for mounting cement mortar harden perfectly, it is not possible to insert electric wires or the like into the pipes.
Especially, in the conventional member for connecting a pipe to a bellmouth, it is difficult to connect the pipe to the bellmouth in such a manner that, after a pipe passage is formed, when an external pressure such as the earth pressure or the like acts on the pipe to thereby apply a tensile force to the pipe in the axial direction of the pipe, such connection can overcome this tensile force to thereby allow the connected portion between the bellmouth and pipe to be free from the damage, that is, the watertight connected condition between them can be prevented against destruction. In other words, according to the conventional pipe and bellmouth connecting member, it is difficult to give the pipe and bellmouth connected portion sufficient resistance to the external force which is applied thereto in the connection removing direction thereof. Also, when there arises a need to detach the pipe from the bellmouth for one reason or another, it is difficult to detach the pipe from the bellmouth; and, as in a case in which a pipe is connected to a bellmouth using a hardening agent solution, it is difficult to detach the pipe in such a manner that the detached pipe can be connected again to the bellmouth without damaging the bellmouth and pipe.
It is an object of the present invention to eliminate the above-mentioned drawbacks found in the conventional connecting member for connecting a pipe to a bellmouth mounted on a hand hole or the like.
Note that the reference numerals given in the drawings corresponding to the embodiments of present invention are added in the explanation below only for the purpose of making an understanding easier.
Accordingly, it is a first object of the invention to provide a bellmouth structured such that the bellmouth itself includes a joint portion formed integrally with an opening thereof to be disposed outside a hand hole, while a pipe to be connected to the bellmouth includes in its connecting end a joint portion corresponding to the joint portion of the bellmouth, and connection of the pipe to the bellmouth can be completed by a very simple one-touch operation, that is, simply by inserting the pipe in the axial direction of the pipe into the bellmouth.
Also, it is a second object of the invention to provide a bellmouth to which a pipe can be connected in a watertight condition by such one-touch operation.
Further, it is a third object of the invention to provide a bellmouth which, it the need arises, allows the connected condition between the pipe and bellmouth to be removed by a very simple operation in such a manner that the thus detached pipe can be connected again to the bellmouth with no fear of being damaged.
The above object can be achieved by a bellmouth with joint, according to a first aspect of the present invention, comprises:
a bellmouth main body X and an engaging ring R produced separately from the bellmouth main body M; the bellmouth main body M including a cylindrical-shaped portion 15 having one opening 16 formed so as to spread in a trumpet-like shape, the other opening of the cylindrical-shaped portion 15 including a guide cylinder 11 capable of connecting a pipe thereto, a large-diameter cylinder portion 12 so formed in the deeper portion of the other opening as to be continuous with the guide cylinder 11 and having a larger diameter than front and rear walls respectively formed before and behind the large-diameter cylinder portion 12 in the axial direction of the pipe, and an outwardly facing projection 14 provided on a portion of the large-diameter cylinder portion 12; the engaging ring R including a guiding inclined surface 31 formed so as to have a C-like non-annular shape when viewed from the side surface thereof, the guiding inclined surface 31 being formed such that the inside diameter of one end face 31a side thereof is large but the inside diameter of the deep side thereof is small, the engaging ring R further including a securing stepped portion 32 formed on the deep side thereof, a plurality of notches 33 respectively formed by cutting out the inclined surface 31, and a projection 34 provided on and projected from a portion of the outer peripheral surface of the engaging ring R, wherein the engaging ring R is inserted into the inside portion 13 of the large-diameter cylinder portion 12 of the bellmouth main body M in such a manner that the large-diameter side end face 31a of the guiding inclined surface 31 is situated on the entrance side of the inside portion 13, and the projection 34 of the engaging ring R is fitted with the inner surface recessed portion of the outwardly facing projection 14 of the large-diameter cylinder portion 12.
In addition, the above-object can also be achieved by a bellmouth, according to a second aspect of the present invention, in which the other opening of the cylindrical-shaped portion 15 includes an inclined cylinder 21 formed so as to be larger in diameter on the deep side thereof than on the end face side thereof, a securing stepped portion 22 formed on the rear surface of the inclined cylinder 21, and a plurality of projecting portions 23 respectively provided in the rear of the inclined cylinder 21.
In addition to this, it is a fourth object of the present invention to provide a system for mounting a bellmouth having the above-mentioned structure onto the wall of a hand hole very easily, quickly and accurately.
This fourth object can be achieved by a concrete block body, according to the present invention, which having a first structure comprises a substantially rectangular-shaped concrete and one or more bellmouths each according to the first aspect of the present invention, and is structured such that, while one or more bellmouths having the first structure are arranged in the same direction, one or more bellmouths having the first structure are buried into the concrete in such a manner that the trumpet-shaped opening(s) 16 of the bellmouth(s) M is or are substantially identical with a given wall surface of the concrete to thereby form an integrally united body as a concrete block body.
In addition to this, the above-mentioned fourth object can also be achieved by a concrete block body, according to the present invention, which having a second structure that comprises a substantially rectangular-shaped concrete and one or more bellmouths each according to the second aspect of the present invention, and is structured such that, while one or more bellmouth(s) having the second structure is or are arranged in the same direction, one or more bellmouth(s) having the second structure is or are buried into the concrete in such a manner that the trumpet-shaped opening(s) 16 of the bellmouth(s) M is or are substantially identical with a given wall surface of the concrete to thereby form an integrally united body as a concrete block body.
Further, it is a fifth object of the invention to provide system capable of installing or setting up a hand hole with the bellmouth having the above-mentioned performance mounted thereon in a given hand hole installation place very easily, quickly and accurately.
This fifth object can be achieved by a hand hole, according to the present invention, having a first structure which comprises one or more bellmouth(s) each according to the first aspect of the present invention, and is structured such that, while one or more bellmouth(s) having the first structure are arranged in the same direction and the trumpet-shaped opening(s) 16 of the bellmouth(s) M is or are substantially identical with the inner wall surface of a hand hole H, one or more bellmouth(s) having the first structure is or are buried into the peripheral wall of the hand hole H to thereby form an integrally united body as a hand hole with a bellmouth.
In addition to this, the fifth object can also be achieved by a hand hole having a second structure which comprises one or more bellmouth(s) each according to the second aspect of the present invention, and is structured such that, while one or more bellmouth(s) having the second structure is or are arranged in the same direction and the trumpet-shaped opening(s) 16 of the bellmouth(s) M is or are substantially identical with the inner wall surface of a hand hole H, one or more bellmouth(s) having the first structure is or are buried into the peripheral wall of the hand hole H to thereby form an integrally united body as a hand hole with a bellmouth.
In enforcing the bellmouth according to the first aspect, the notches 33 in the ring R may be formed in such a manner that it includes one inclined surface 33a on one side thereof or two inclined surfaces 33a respectively on both sides thereof in the circumferential direction of the ring R, and only the other opening of the bellmouth, that is, only the opening on the side of the bellmouth that is situated outside the wall of a hand hole may be covered with a closing cover formed integrally therewith, or both of the inside and outside openings of the bellmouth may be respectively covered with their associated closing covers formed integrally therewith, thereby holding the bellmouth in a sealed manner.
Also, in enforcing the bellmouth according to the second aspect of the invention, the waterproofing ring 25 may be provided on the deep portion of the projecting portions 23 formation portion of the bellmouth, each of the projecting portions 23 may include one inclined surface 23a on one side thereof or two inclined surfaces 23a respectively on both sides thereof in the circumferential direction of the bellmouth, and only the other opening of the bellmouth, that is, only the opening on the side of the bellmouth that is situated outside the wall of a hand hole may be covered with a closing cover formed integrally therewith, or both of the inside and outside openings of the bellmouth may be respectively covered with their associated closing covers formed integrally therewith, thereby holding the bellmouth in a sealed manner.
Further, in enforcing the hand hole having the first structure or the second structure according to the invention, preferably, the hand hole may be enforced in such a manner that the bellmouth(s) is or are buried into the two mutually opposing peripheral walls of the hand hole H.
When connecting a pipe P set forth in embodiments to be discussed later to the above-structured bellmouth, such connection can be completed by a very simple one-touch operation, that is, simply by pushing the pipe P in the axial direction thereof into the bellmouth.
Also, when there arises a situation to detach the thus connected pipe from the bellmouth, the connected condition between the pipe and bellmouth can be removed by a simple two-stage operation, that is, by rotating the pipe slightly in the peripheral direction thereof with respect to the bellmouth and, after then, pulling out the pipe as it is in the axial direction thereof from the bellmouth.
The present disclosure relates to subject matter contained in Japanese Patent Application No. Hei. 10-322464, filed on Nov. 12, 1998, and which is expressly incorporated herein by reference in its entirety.